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Electron-molecule collisions are among the most fundamental processes in gas discharges. They are also the precursors of the ions and the radicals which drive the etch, cleaning, or deposition processes in plasma reactors. Hence, there is a need for a
Relative intensities and translational ion-flux energy distributions are presented for negative ions sampled from Townsend discharges in O 2, SF 6, and CF 4 for a high range of density reduced electric fields greater than 2 W 10 -18 V m 2 (> 2 kTd). These
We report ion energy distributions, relative ion intensities, and absolute total ion current densities at the grounded electrode of an inductively coupled Gaseous Electronics Conference radio-frequency reference cell for discharges generated in pure C 4
Huibin Zhu, Jih-Sheng Lai, Yi-hua Tang, Allen R. Hefner Jr., Celia Chen
For the purpose of investigation of electromagnetic interference (EMI) mechanisms in PWM inverters, empirical models and comparative experiments were studied in both time and frequency domains. Models of major circuit components including switching devices
Application of a compliant, low modulus dielectric layer between the chip joints (C4) and the carrier can decrease the thermally induced bending and probability of failure. Model analysis and experimental data indicate that the optimal thickness of the
Yicheng Wang, Loucas G. Christophorou, James K. Olthoff, J. K. Verbrugge
Measurements are reported of the electron drift velocity, w, in CHF 3 gas and in its mixtures with argon. The E/N dependence of w in the mixtures exhibits regions of distinct negative differential conductivity. A small electron attachment rate constant (-
We report ion energy distributions, relative ion intensities, and absolute total ion current densities at the grounded electrode of an inductively-coupled Gaseous Electronics Conference radio-frequency reference cell for discharges generated in pure argon
Low energy electron interactions with the Cl 2 molecule are reviewed. Information is synthesized and assessed on the cross sections for total electron scattering, total rotational excitation, total elastic electron scattering, momentum transfer, total
Translational flux-energy distributions of positive and negative ions have been measured at high electric field-to-gas density ratios (E/N) up to 40 x 10 -18 V m 2 (40 kTd) in diffuse, parallel-plate Townsend discharges in oxygen using an ion energy
Dylan F. Williams, Christopher L. Holloway, Janet E. Rogers
This paper investigates a measurement method that characterizes lossy printed multiconductor transmission lines, its accuracy, the choice of measurement representations, and some simple approximations. We illustrate the method with measurements of a pair
S. G. Walton, J. C. Tucek, R. Champion, Yicheng Wang
Absolute yields of electrons and negative ions resulting from positive ions impacting stainless steel have been determined as a function of impact energy for clean and oxygen-covered surfaces. Photoelectron emission has been used to monitor the effect of
J. W. Allen, Fred R. Clague, N T. Larsen, M. P. Weidman
The National Institute of Standards and Technology (NIST) microwave power standards in waveguide consist of automated microcalorimeters and associated transfer standards. Each transfer standard is a bolometric dc substitution power detector (a thermistor
The transport of positive and negative ions plays an important role in the initiation and behavior of discharges in gaseous dielectrics. In many cases, the identities, intensities, and kinetic energies of ions are determined by ion-molecule collisions
Gary D. Cooper, Jason E. Sanabia, J. H. Moore, James K. Olthoff, Loucas G. Christophorou
Absolute measurements of the total electron scattering cross section for chlorine, Cl2, are reported for electron energies ranging from .3 eV to 23 eV. The present data are in reasonable agreement with previous measurements of the cross sections for total
The significance of interconnect parasitics of power electronics system is their affects on converters' EMI-related performances, such as voltage/current spikes, dv/dt, di/dt, conducted/radiated EMI noise, and the like. In this paper, a time domain refle
Chien-Chung Shen, Allen R. Hefner Jr., David W. Berning, J B. Bernstein
The internal failure dynamics of the Insulated Gate Bipolar Transistor (IBGT) for unclamped inductive switching (UIS) conditions are studied using simulations and measurements. The UIS measurements are made using a unique, automated nondestructive Revers
Many advanced plasma diagnostic techniques and plasma models require fundamental physical data in order to make accurate measurements or predictions. Fundamental electron-interaction data are among the most critical since electron collisions are the
Lawrence P. Dunleavy, James P. Randa, Dave K. Walker, Robert L. Billinger, John Rice
A set of wafer-probeable diode noise source transfer standards are characterized using on-wafer noise-temperature methods developed at the National Institute of Standards and Technology (NIST), Boulder, CO.
Yicheng Wang, Loucas G. Christophorou, James K. Olthoff, J. K. Verbrugge
Measurements are reported of (i) the electron drift velocity in pure trifluoromethane (CHF 3) gas and in its mixtures with argon, and (ii) electron attachment in pure CHF 3. The E/N dependence on the electron drift velocity in mixtures exhibits regions of
Yicheng Wang, Loucas G. Christophorou, J. K. Verbrugge
The effect of temperature on electron attachment to dichlorodifluoromethane (CCl 2F 2) has been investigated for temperatures up to 500 K and for mean electron energies from thermal to 1.0 eV using an electron swarm method. The measurements were made in